Take the ruler and place it so that it is half on the table and half off.

Firmly hold the part of the ruler that is on the table. Use your other hand to pull up on the part of the ruler that is off the table.

Let go and listen to the sound. Keep repeating this action, testing out ways to make higher and lower sounds by moving the ruler.

I then asked Sinister why he thinks this happens:

“It’s all the energy in the ruler. You flick the ruler and it puts energy in the ruler, so the ruler tries to shake the energy out.”

That’s the 6yo definition of ‘vibration’.

And of course, Sinister wants to take it a step further. So he keeps flicking it. Hard… And the ruler breaks. *sigh* Rather than waste good science-time being mad at him, I simply ask why he thinks the ruler broke.

“Well, there was too much energy in the ruler. It couldn’t handle it. So it broke. That was the best way to release the energy.”

I’m pretty sure he is talking about the snappy ruler experiment, and not The Snappy Ruler (me).

His punishment – to write a science report explaining what happened and the steps he took. Not really a punishment – more a lesson in the steps of science. And he only protested a little. Three sentences seems fair to both of us. Nefarious draws a ‘picture’. I’m pretty sure it is the ruler exploding, but his minimalist approach leaves a bit to the imagination.

While writing his report, Sinister turns and asks

“Is Lego Batman’s sonar gun like the ruler?”

He then starts asking me about vibrations, directed sound, and frequencies. Although the discussion starts innocently enough, both boys seem fascinated with police using sonic weapons against protesters. Nefarious starts to ask how many rulers need to shake in our bellies before we stop being naughty. Sinister asks how many machines would be needed to control the minions.

I suddenly see a glimpse of where these Forensic Fridays are taking my children… and I sniff back my pride and excitement, lest they see it as a moment of weakness and attack.